1. Field of the Invention
The present invention relates to tools, specifically to a key for gas cylinders.
2. Description of the Related Art
A gas cylinder is a pressure vessel used to store gases at above atmospheric pressure. High pressure gas cylinders are also called bottles. Although they are sometimes colloquially called “tanks”, this is technically incorrect, as a tank is a vessel used to store liquids at ambient pressure and often has an open top. An oxygen tank is a storage vessel for oxygen, which is either held under pressure in gas cylinders or as liquid oxygen in a cryogenic storage tank.
Oxygen tanks are used to store gas for: industrial processes including the manufacture of steel and monel; oxyacetylene welding equipment and some gas cutting torches; use as the liquid rocket propellants for rocket engines; medical breathing gas at medical facilities and at home; breathing at altitude in aviation, either in an uncontrolled decompression emergency, or constantly (in the case of unpressurized aircraft); oxygen first aid kits; gas blending for creating diving breathing mixes such as nitrox, trimix and heliox; open-circuit scuba sets—mainly used for accelerated decompression in technical diving; some types of diving rebreather: and oxygen rebreathers and fully closed circuit rebreathers.
When gases are supplied in gas cylinders, the cylinders have a stop angle valve at the end on top. Often, gas cylinders are somewhat long and narrow and may stand upright on a flattened bottom at one end with the valve at the top. During storage, transportation, and handling when the gas is not in use, a cap may be screwed over the protruding valve to protect it from damage or breaking off in case the cylinder were to fall over. Instead of a cap, cylinders commonly have a protective collar or neck ring around the service valve assembly.
When the gas in the cylinder is ready to be used, the cap is taken off and a pressure-regulating assembly is attached to the stop valve. This attachment typically has a pressure regulator with upstream (inlet) and downstream (outlet) pressure gauges and a further downstream needle valve and outlet connection. For gases that remain gaseous under ambient storage conditions, the upstream pressure gauge can be used to estimate how much gas is left in the cylinder according to pressure. For gases that are liquid under storage, e.g., propane, the outlet pressure is dependent on the vapor pressure of the gas, and does not fall until the cylinder is nearly exhausted. The regulator could be adjusted to control the flow of gas out of the cylinder according to pressure shown by the downstream gauge. The outlet connection is attached to whatever needs the gas supply, such as a balloon for example.
The valves on industrial, medical and diving cylinders are usually of different size and type, as are the valves for different products, making it more difficult to mistakenly misuse a gas. Some fittings use a right-hand thread, while others use a left-hand thread; left-hand thread fittings are usually identifiable by notches cut into them.
Some improvements have been made in the field. Examples of references related to the present invention are described below in their own words, and the supporting teachings of each reference are incorporated by reference herein:
U.S. Pat. No. 8,087,639, issued to Knapp, discloses an oxygen tank key includes an elongated substantially thin flat handle portion defining a first plane and having first and second ends that define the length thereof and first and second side edges that define the width. A socket, integrally formed with the handle portion between the two ends, has a thickness that is greater than the thickness of the handle portion. The socket includes an aperture that opens adjacent one of the side edges and has a depth extending substantially the width of the handle portion. The aperture has a substantially rectangular cross-section and is adapted to fit onto the rectangularly shaped end of an oxygen tank valve control stem. A slot passes through the handle and is elongated in the direction of the length of the handle. The slot includes champhered ends and is adapted to fit over the lever of a regulator for the oxygen tank to help release the regulator from the tank.
U.S. Pat. No. 6,899,001, issued to Sanders et al., discloses a multiple component wrench is adapted for use to attach and disconnect fire hose and hydrant coupling using this singular tool in lieu of several tools currently used by firefighters. The wrench has a sliding portion and a receiver portion presented as one tool, yet allowing multiple wrenches adapted for use on Storz and spanner hose couplings, rocker lug couplings, water meter shutoff valves, gas cock valves, pentagonal nuts and square nuts, and includes a multiple ratchet mechanism with multiple removable ratchets adapted to a variety of different nuts encountered on the multiple hydrants installed in various municipalities. The wrench is also extendable to provide additional leverage during use, the wrench further capable of separation forming two independent wrenches.
U.S. Pat. No. 6,450,069, issued to Brahmbhatt, discloses a multi-purpose wrench (10) used to open valves (V) on gas cylinders of various sizes. An elongate handle (12) has a ratchet formed at one end (12a). A socket (14) mounts on the ratchet and has a plurality of openings (20a,22a, 20b,22b) formed on opposite surfaces (18a, 18b) for engaging the stem of a valve (V3, V4) to open and close the valve. A disc (26) is attached to a ratchet (24) adjacent the other end of the handle to open gas cylinders of a different size. The disc includes a plurality of pins (28) which engage differently shaped wheels of valves (V1, V2) the wrench to open the valve when rotated.
U.S. Pat. No. 6,076,435, issued to White Sr. et al., discloses a tool for multiple purposes including turning valve wheels, opening drum plugs and vents, driving sockets, turning screws, use as a drift pin and prying, among other possible uses, the tool having a handle and an exterior shank and an interior shank, each shank having a square cross section and being in a spaced relationship and parallel to one another located at one end of the handle, the opposite end of the handle having an edge and the handle being tapered, the interior shank which is located furthest from the end of the handle having an outer end with a reduced size set off center so that the wall of that shank toward the edge is aligned along the entire interior shank.
U.S. Patent Application Publication No.: 2010/0122419, by Zupancic-Albin, discloses a multi-function tool designed for the needs of healthcare professionals. The multi-tool may include individual tools that a healthcare professional uses on a regular basis, including a gas cylinder wrench, an integrated pill slicer, a set of EKG calipers, a sharp/dull neurological response tester, and a gripping device for I.V. caps. Additional features may include a penlight or laser pointer and a fold out ruler. A tool carrier includes features that healthcare professionals also regularly use, such as a tape roll holder and dispenser and retractable ring for keys and security badges.
The inventions heretofore known suffer from a number of disadvantages which include being ineffective, being inefficient, being difficult to use, being limited in use, being limited in functionality, failing to provide universal access to a plurality of gas cylinders/tanks, failing to assist a user where a washer/o-ring is missing, requiring multiple tools, making life difficult for those in compromised health situations, and requiring too much hand strength, especially from children and the elderly.
What is needed is a gas cylinder key that solves one or more of the problems described herein and/or one or more problems that may come to the attention of one skilled in the art upon becoming familiar with this specification.